Magazine

The War On Cancer: Reports From The Front

June 17, 2007

More than 31,000 doctors and researchers attended the American society of Clinical Oncology's annual meeting on June 1-5 in Chicago. They discussed advances in cancer research that could soon transform how patients are treated. Here are some of the latest data:

Genentech's (DNA) breakthrough drug Avastin proved that shutting off the blood supply to a tumor can stop the spread of cancer, a process called anti-angiogenesis. Now several other such drugs are in the pipeline.

VEGF-Trap, developed by Regeneron Pharmaceuticals (REGN) and Sanofi-Aventis (SNY), works like Avastin and may be even safer for patients. In a mid-stage study involving 153 patients with advanced ovarian cancer, it stopped the cancer from progressing in 71% of patients and shrank tumors in 8%. Only 1% of patients on VEGF-Trap developed potentially fatal bowel perforations, compared with 11% on Avastin.

Pfizer (PFE) also presented data on its anti-angiogenesis drug, Axitinib, aimed at thyroid cancer, for which there have been no new medicines in over 30 years. In a trial with 60 people, it shrank tumors in 13 patients.

Certain cancer cells are determined to survive and spread and will adapt to very toxic environments if they have to. Consequently, tumors frequently develop resistance to all manner of drugs over time--often by activating a protective cellular mechanism called heat shock protein 90, which acts as a bodyguard for cells under attack. Several companies are testing drugs that hold HSP90 in check so that cancer treatments can do their work.

Dr. George Demetri of Dana-Farber Cancer Institute has had success with an anti-HSP90 drug from Infinity Pharmaceuticals (INFI) called IPI-504, being tested on patients resistant to Gleevec, a Novartis (NVS) treatment for stomach cancer. Demetri says he would like to study it more broadly. And Kosan Biosciences (KOSN) is testing two anti-HSP90 drugs against four different cancers. Early-stage trials persuaded Kosan to enter a larger Phase 3 trial this summer. "We may have the first HSP90 inhibitor to reach the market," says Kosan's CEO, Dr. Robert Johnson.

-- Not all studies at the cancer meeting were about drugs. Researchers at Duke University presented results of a trial involving 161 men with prostate cancer, some of whom were helped by a diet that included a daily 30-gram dose of flaxseed, a grain rich in Omega-3 fatty acids. After 30 days, the researchers observed that cancer cells in the men taking flaxseed grew 30%-40% more slowly than cells in the control group. Further studies are needed before they can recommend the grain.

-- A number of companies presented data on therapeutic cancer vaccines, meant to prod the body's own immune system into attacking tumors. Although such vaccines have been studied for years, they have been difficult to test, and most are still in the early stages of development. Three vaccines against lung cancer, from GlaxoSmithKline, IDM Pharma (IDMI), and Introgen Therapeutics (INGN), produced promising enough results in early-stage trials to merit further testing.